Strand traversing device



P 3, 1968 s. R. GENSON 3,399,841

STRAND TRAVERSING DEVICE Filed Dec. 21, 1965 INVENTOR. SAMuQR/c/MRD Gzuso/v United States Patent 3,399,841 STRAND TRAVERSING DEVICE Samuel Richard Genson, Bowling Green, Ohio, assignor to Johns-Mauville Corporation, New York, N.Y., a corporation of New York Filed Dec. 21, 1965, Ser. No. 515,349 Claims. (Cl. 24243) ABSTRACT OF THE DISCLOSURE A strand traversing mechanism comprised of a cylindrical member with the curved surface of the member engaging the strand. The member being rotated about an axis which is oblique to the longitudinal axis of the member.

This invention relates to the traversing of strand material as it is being wound upon a winding core. More particularly, this invention relates to automatic traversing mechanism which is adaptable to operate in conjunction with automatic machinery for winding continuous filaments or strands.

While the method and apparatus of this invention are not necessarily limited for use with any particular strand, it is particularly adapted for use with the formation of heat-softenable continuous filaments, such as glass, and hence will be described in connection therewith.

Continuous glass filaments are usually produced by attenuating exudations formed at the discharge orifices of a glass melting receptacle. The attenuation means usually comprises the winding upon which the continuous filaments are wound to form a strand package. Between the melting receptacle and the winding core is positioned a converger for converging a plurality of filaments, in the presence of a lubricant, binder, or other treating material, into a strand. Then between the converger and the winding core is usually positioned a fast traverser for alternately traversing the strand across the face of the package being formed.

The great majority of traversing mechanisms presently employed in connection with glass filament winding are of the wire cam type. In one such type of traverse, such as disclosed in US. Patent No. 2,391,870, Beach, a pair of opposed and conical spiral cams are supported upon a rotating shaft; the cams complement each other in a manner whereby each alternatively engages and progresses the strand across the face of the package being formed. In another type of wire cam traverse, as disclosed in U.S. Patent No. 3,040,999, Hayden et al., complementary sets of wire cams are provided; a first set of cams progresses the strand along the periphery of the strand package support and another set of cams regresses the strands.

The wire cam type of rotating traverse is not completely satisfactory for the reason that the strand is alternately shifted from one strand engaging member of the traversing mechanism to another. Such alternate engagement produces undue abrasion and tension variation in the strand. Furthermore, such traversing mechanisms are relatively weak structurally and are more susceptible to damage in the event of a support tube blow-up. High speed photographs of traversers having a plurality of cams mounted for rotation about a common axis disclose that nodes are sometimes produced, a node being a position where the strand resists traversing movement, at least momentarily. Hence, the strand tension is unduly disrupted and the possibility of abrasion is also increased. Uneven tension results in filaments being produced which are not of constant diameter and abrasion reduces the tensile strength of the filaments.

ice

It has heretofore been suggested, US. Patent No. 2,989,258, Margason, to provide a single wire cam traversing mechanism. The mechanism includes a wire rod portion in the form of a Z with successive portions of the rod being laterally offset from the axis of rotation, first on one side of the axis and then on the other side of the axis. In such an arrangement the strand tension is varied from a maximum when the strand is on one side of the axis of rotation to a minimum when the strand is on the opposite side of the axis of rotation.

Generally speaking, it has been found that the disadvantages of the wire type of rotating traversing mech anism may be obviated by the provision of a rotating traversing element which continuously engages the strand being Wound, which traversing element is more structurally sound than the wire cam type of traverse. Such traversing element, in a preferred embodiment, being in the form of a cylinder, having a relatively large diameter as compared to the arm supporting the cylinder, and supported for rotational movement about an axis of rotation which is oblique to the longitudinal axis of the cylindrical member.

In a preferred embodiment of this invention, a plurality of continuous filaments are attenuated from a plurality of exudations formed at the discharge orifices of a glass melting receptacle; the filaments are Wound as a strand upon a winding core positioned on a rotating mandrel; between the mandrel and the melting receptacle the filaments are converged into a strand at a converger whereat a lubricant or other liquid treating material is applied to the filaments as they are converged; between the converger and the mandrel the strand is engaged for fast or primary traverse movement by a rotating strand engaging element mounted for rotation about an axis inclined in the general order of 3045 from the longitudinal axis of the strand engaging element; and the mandrel is preferably reciprocally mounted to impart a slow traverse to the strand across the face of the package being formed. Consequently, as the strand advancing from a source is subjected to the fast traversing force, the strand defines a bight within the amplitude of the reciprocating or sliding movement across the face of the strand engaging member and as the strand is concomitantly subjected to the unidirectional slow traversing action a series of bights are formed which advance uni-directionally across the face of the mandrel or package.

It is an object of this invention to provide a new and improved apparatus for forming a continuous filament package, which apparatus obviates the disadvantages of the prior art.

It is another object of this invention to provide method and apparatus for traversing a strand in an arrangement whereby the strand may be continuously engaged by one strand engaging element of the traversing mechanism throughout the .formation of a single strand package, thereby avoiding the need for transfer from one strand engaging element to another and the concomitant disadvantages.

It is a further object of this invention to provide a traversing mechanism which is structurally more sound than traversing mechanisms of the single wire cam type.

It is a still further object of this invention to provide a traversing mechanism which obviates the tens'ional variations of traversing mechanisms whereby a strand being wound is alternately tra'versed across the axis of rotation of the traversing mechanism.

The invention will be better understood from the following description of species thereof when taken in conjunction with the drawings.

FIG. 1 is a schematic front elevational view of apparatus for forming a package of continuous glass filaments utilizing a traversing mechanism embodying the invention;

FIG. 2 is a side elevational view of the traversing mechanism of FIG. 1;

FIGS. 3-6 are plan views of the primary traverse of this invention, which views schematically illustrate the movement of the strand on the traverse mechanism during the rotation of the traverse;

FIG. 7 is a plan view of an embodiment employing a hollow cylinder as the traversing head;

FIG. 8 is a plan view of an alternate embodiment of a traversing head; and

FIG. 9 is a schematic front elevational view of apparatus for forming a package comprised of plural strands.

Referring to FIG. '1, the primary or fast traversing mechanism, generally indicated by numeral 10 is shown in connection with apparatus for forming continuous glass filaments comprising a glass melting receptacle 12 from which a plurality of exudations 14 are exuded. The exudations 14 are attenuated into a plurality of filaments 16 by means of a rotating core or spool 18 mounted for rotation on mandrel 20; the filaments 16 are converged into one or more strands 22 by one or more corresponding convergers 24. Liquid treating materiai, such as lubricants, binders, sizes, or the like, may be applied to the filaments 16 as they are converged and to the converger 24 by means of a head 26.

The primary traversing mechanism 10, which will be described in more detail hereinafter, is positioned to engage the strand 22 between the converger 24 and the mandrel 20.

The tubular core 18, which serves as the base for the package being formed, is removably mounted on mandrel 20 for rotation therewith. Mandrel 20 is shown to be supported by and rotatable with shaft 28 driven by motor 30. Motor 30 is suitably mounted for reciprocation upon guide 32 in a direction 34 parallel to the axis rotation of mandrel 20. The reciprocation of motor 30 may be accomplished by suitable known means (not shown). Such reciprocation of motor 30 and consequently of core 18 effects a secondary or slow, traverse movement of the strand 22 across the face of the package being formed. Primary traverse 10 effects a series of progressive and regressive bights across the package being formed whereas the secondary traverse effects a unilateral progression of the series of bights to form a layer extending the length of the package to be formed.

The primary traverse mechanism 10 comprises a strand engaging or traverse head member in the form of a cylinder 40, which may be solid as shown in FIGS. 3-6, or hollow as shown in FIG. 7. The cylinder is suitably secured to arm 42 which forms an extension of rotatable shaft 44 of motor 46. Cylinder 40 is preferably supported so that its longitudinal axis 48 forms an acute angle 5 with the axis of rotation 50 of arm 42 in the order of 30-45 degrees. The cylinder 40 is oriented to engage a strand 22 with slight tension (as may be seen in FIG. 2) throughout the rotational movement of cylinder 40. Tensional engagement of the cylinder 40 tends to deviate the strand 22 advancing from converger 24 to core 18 from an absolutely straight path. As the cylinder 42 rotates, the strand 22 seeks to maintain a position approaching a straight path and slides along the highly polished surface of the cylinder 40 to impart an incremental lateral movement across the face of the package being formed, which movement may be in the order of three inches.

The traverse head 40 defines an effective traversing area, on its continuously rotating surface, along which the strand 22 slides lengthwise of the head 40 but is maintained on one side of a vertical plane, at the traversing head, extending through and in the same direction as the linear extent of the axis of rotation of the traversing head.

It is preferred to maintain a ratio of traverse head cylinder 40 diameter to support arm 42 diameter (transverse width) of at least 3 to 1 so that sufiicient axial length is provided, in an area of the cylinder 40 which is spaced away from the support arm 42, along which a strand may slide without being contacted by arm 42. However, the diameter of cylinder 40 should be so great as to establish greater line contact of the cylinder surface with the strand than is necessary to perform the traversing function.

The degree of strand traverse may be varied by changing the diameter of the cylinder, the angle of the cylinder, or less preferably, by changing the diameter of the arm 42. In a preferred embodiment, a right circular cylinder 40 having a diameter of 2 inches and a length of 5 inches is supported on arm 42 to form an acute angle in the general order of 40 between the longitudinal axis of the cylinder 40 and the axis of rotation 50. The cylinder 40 in the preferred embodiment is supported by an arm 42 having a diameter in the general order of inch. The surface of the cylinder 42 is preferably of a material having a low coefi'icient of friction and is highly polished to resist abrasion of the strand being wound. The cylinder 40 may be suitably formed from highly polished brass tubing or from one of the metallized carbon graphite materials commercially available through suitable sources such as, and as more fully described in a brochure of, the Metallized Carbon Company, Inc., Ossining, NY.

The relative position of the strand 22 as it is being traversed in respect to the cylinder 40 as it rotates may be observed in FIGS. 3-6. FIG. 3 represents what may be termed the neutral position of cylinder 42, or at 0 and 360 of rotation. As the cylinder 40 is rotated a strand 22 slides across the surface of the cylinder 40 and at of rotation of cylinder 40 (FIG. 4) the strand assumes a medial position. As the cylinder 40 is further rotated the strand slides across the surface and completes the progressive motion when the cylinder 40 is rotated to the position shown in FIG. 5. Then as the cylinder 40 is further rotated the strand begins its regressive motion and assumes a medial position when the cylinder is in the 270 position (FIG. 5) and completes the regressive motion at the 360 or 0 position of the cylinder 40 (FIG. 3).

From the above description and from viewing the drawing, it is apparent that the strand 22 stays on one side of the axis of rotation 50. The maximum deviation in tensional forces is represented by the strand when it reaches the 90 or the 270 position. Thus, it will be noted that this deviation is only /2 of the deviation that would occur if the strand were traversed by a member which permits the strand to cross the axis of rotation.

FIG. 7 illustrates the manner in which a hollow cylinder 40A may be supported by means of support tube 60 extending through the interior of the cylinder 40A and which tube 60 may be secured to arm 42.

FIG. 8 illustrates one manner in which the weight of a traversing head 400 may be reduced by modifying the terminal ends 62 and 64 by omitting portions 66 and 68 (shown in phantom lines) 'which do not make contact with a strand while it is being traversed.

FIG. 8 also illustrates the arcuate side 70 as being curved in an axial direction as well as in a radial sense and provides an illustration of a non-right circular type of cylinder.

It is to be understood that the term cylinder as used in this specification and in the claims is not restricted to cover only a right circular cylinder but is intended to cover solids of revolution and other body forms having a longitudinal axis and which present a surface curved generally in the direction of the strand path when supported in the manner indicated in the drawing and modifications of such bodies as frustums, ungulae, etc.

It should be pointed out also that the cylinder is relatively more sound structurally than wire cam members that have been heretofore predominantly employed as traversing members. Thus, a comparatively rigid member is provided in this invention which can be harmonically balanced and which can withstand forces, and thus avoid damage, caused by the occasional bursting of the cores 18. Cores 18 are usually made of paper or plastic material which upon repeated wetting by excess liquid treating material dropping from converger 24 and subsequent drying become weakened. When such cores 18 are positioned on expansible mandrels 20 and brought up to rotating speed they occasionally burst and explode from the mandrel with great force.

The instant invention finds particular utility for producing plural strand packages wherein a number of strands comprised of a multiplicity of filaments are drawn from a single source and the several strands are wound onto a package in spaced apart relation, as illustrated in FIG. 9. Since the strands are subjected to the traversing action of a single cam member, as opposed to traversing mechanisms which employ several cams and whereby the strand is transferred from one cam to another, there is little tendency for the several strands to become entangled or cross over at the end of a progressive or regressive motion.

What I claim is:

1. Rotatable traversing mechanism for moving a strand being wound along the axial extent of a strand package being formed, which traversing mechanism comprises:

a strand engaging member having a curved surface defined by a cylindrical portion, having a longitudinal axis, and being supported for rotational movement about an axis of rotation which is oblique to said longitudinal axis,

said member being supported to define an effective traversing surface area along which said strand slides lengthwise of said member but on one side of a vertical plane extending through and in the same direction as said axis of rotation.

2. A mechanism as described in claim 1, which further comprises:

a rotatable support arm supporting said member and having a relatively small cross-sectional width as compared with the diameter of said cylindrical portion.

3. A mechanism as described in claim 2 wherein:

said support arm has a circular cross-section, and said cylindrical portion has a diameter at least three times that of the diameter of said support arm.

4. A mechanism as described in claim 1 wherein:

the acute angle between said axis of rotation and said longitudinal axis is in the range of 30-45.

5. A mechanism as described in claim 1 wherein:

the acute angle between said axis of rotation and said longitudinal axis is in the general order of 40.

6. A mechanism as described in claim 1 wherein:

said member is comprised of bronze carbon.

7. A mechanism as described in claim 1 wherein:

said member is comprised of brass tubing.

8. A mechanism as described in claim 1 wherein:

said member is comprised of metallized carbon graphite.

9. Apparatus for traversing a strand while it is being advanced in a path which comprises:

a cylinder having a longitudinal axis and defining a surface curved in the same general direction as said path, and for establishing contact with said strand, said cylinder being mounted for rotational movement, about an axis of rotation which is oblique to said longitudinal axis, by a support arm having a relatively small diameter as compared to the diameter of said cylinder; and

means for rotating said arm.

10. The method of winding glass fiber strands which comprises, in combination:

providing a plurality of glass fibers;

advancing said fibers in generally longitudinal paths and converging said fibers to form a plurality of separate strands;

engaging said strands with a moving curved surface having a longitudinal axis while maintaining said strands in spaced relation with each other along said curved surface, rotating said curved surface in a direction generally corresponding to the direction of said paths but about an axis which is oblique to said longitudinal axis of the member defining said surface, to impart a progressive and regressive traversing motion to said strands; and

collecting said strands into a common package.

References Cited UNITED STATES PATENTS 2,386,158 10/1945 Collins 242-42 2,391,870 1/ 1946 Beach 242-43 2,989,258 6/ 1961 Margason 242--43 3,169,717 2/ 1965 Fox et al. 242-43 3,356,304 12/ 1967 Genson 24243 STANLEY N. GILREATH, Primal Examiner. 

